Greentherm Delivers High-Temperature Hitachi Heat Pump Solution for DX Living Project
Founded in 2007 to bring renewable energy to the Irish market, Greentherm Ltd quickly mastered turnkey installation of heating, hot water, ventilation, and controls for commercial and residential projects.
Eight years ago, Greentherm shifted focus to distribution and importing with an extra dimension that made it unique in the Irish market, an expert design support service to complement the services provided by consulting engineering and contracting clients.
Today, the team’s deep, practical knowledge ensures that clients get not only top-quality global products but also a service that anticipates and solves the real-world installation challenges inherent in complex renewable/ mechanical projects. Its deep project history gives it an unmatched, precise understanding of system engineering and a breadth of knowledge and experience to deliver the most complex HVAC solutions for clients.
DX Living Project
One recently completed project is a perfect example of how its solutions-driven approach is delivering results for clients. The DX Living project in Donnybrook is a co-living development offering shorter-term accommodation, typically for company employees on secondment.
The objective of the project was to provide renewable domestic hot water production using heat pump technology. The solution had to be able to cover the building’s peak demand of around 3,000 litres per hour, while also being scalable for low-demand periods, to ensure the system provided economic operation.
The heat pumps had to be capable of heating the domestic water to 65°C for sterilisation, without the use of costly electrical immersion heaters. An additional consideration was to have a low output turndown to maintain the energy requirement for the secondary return without constant short cycling of the system compressors.
Hitachi heat pump solution
Greentherm set about selecting the key elements of a heat pump, hot water storage, and an integrated control system, using design parameters provided by consulting engineers, O’Connor Sutton Cronin.
The heat pump element of the solution was to utilise a cascade bank of four Hitachi S80 high-temperature heat pumps, capable of operating at flow temperatures of up to 80°C. The two-stage compressor units can maintain heat output down to their lowest operating temperature of -20°C.
The hot water storage was sized, resulting in the selection of three Lapesa GX6-DE1000 tank-in tanks. Each tank contains a 712-litre inner tank manufactured in 316L marine-grade stainless steel encased in moulded polyurethane foam. The volumetric balance in the outer tank provides buffer storage and hydraulic separation for heat pumps. In order to provide correct system balancing of each of the Lapesa tank in tanks, Brandoni EKOFLUX Pressure Independent Control Valves (PICVs) were utilised to balance and provide zone control to each calorifier.
In conclusion
The Greentherm package provided on the DX Living project included sourcing the optimum heat pump and water storage unit mix and all controls for the system. It then wrote the control programme before installing, testing, validating and commissioning all plant and controls.
Greentherm is in a unique position to provide this specialist value-added service to clients and works closely with project consulting engineers to ensure all programme goals are met. For more details, phone 01 531 4781, email info@greentherm.ie or visit www.greentherm.ie
PROJECT SUMMARY
Consulting Engineer: O Connor Sutton Cronin
System Design: Greentherm Ltd
Heat Pumps: Hitachi S80 high-temperature heat pumps
Hot Water Storage: Lapesa GX6- DE1000 tank in tanks
Controls: DEOS AG EMS 600 Open protocol Controller
Control Valves: Brandoni EKOFLUX PICVs